Present continuous/simple

It's really awkward when she does it, especially when we wait in a line.
It's really awkward when she does it, especially when we're waiting in a line.
It's really awkward when she's doing it, especially when we're waiting in a line.
It's really awkward when she's doing it, especially when we wait in a line.

People always stare at me when I'm not wearing a shirt.
People always stare at me when I don't wear a shirt.
People are always staring at me when I'm not wearing a shirt.
People are always starting at me when I don't wear a shirt.

Are there any differences between the sentences above? If so, what are they? Thanks.